1. Field of the Invention
This invention relates to a vibration damper for rotating drilling tubes on deep-drilling machines, comprising an annular flywheel.
2. Description of Prior Art
Vibration dampers of this kind are known and are intended to damp or suppress drilling vibrations by the slip between the flywheel and the drilling tube. The frictional contact between the flywheel and the drilling tube can be adjusted by a clamping sleeve, through the agency of adjusting members, for optimum damping or suppression of the vibrations according to present conditions. The drilling tube support bearing, which carries the vibration damper is mounted adjustably on a machine support and can be brought into any desired position by means of a hand crank, in order thus to provide optimum support and damping of the drilling tube. In the known vibration dampers, the adjusting members each engage a tapped bore in the flywheel by means of an external screwthread and rotate together with the mass. It is therefore practically impossible to adjust the clamping sleeve during drilling, i.e. when the drilling tube is rotating and hence when the flywheel mass is rotating.